Plotting-indicator.



E.. A. SPERRY.

PLUTTING INDICATOR.

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Patented Feb. 13, 1917.

ll Il WTNESSES W A o ...5...

@y @my E. A. SPERRY.

PLOTTING INDICATOR.

APPLICATION msn nec. is, 19u.

Patented Feb. 13, 1917.

3 SHEETS-SHEET 2.

INVENTOR.' ELMER ASPERRY, BY

WITNESSES mfg@ m: Naam: uns w.. Nam-uma wAsnmcmN. n. c.

E. A. SPERRY.

PLOTTING INDICATOR.

APPLICATION FILED nic. la, 1914.

Patented Feb.13,1917.

3 SHEETS-SHEET 3.

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ELMERASPEHRY BY MAM J tij ATTORNEY. l

UNTTED sTATEs PATENT oEEIoE.

ELMEB. A.. SPERRY, OF BROOKLYN YORK, ASSIGNOR T0 THE SPERRY GYROSCOPECOMPANY, lOIE NEW YORK, N. Y., A CORPORATION 0F NEVJ YORK.

PLOTTING- INDICATOR.

Specification of Letters Patent.

Patented Feb. 13, 1917.

To all whom t may concern.'

Be it lcnownthat I', ELMER A. SPERRY, a citizen of the United States ofAmerica, residing at 100 Marlborough road, Brooklyn, New York, haveinvented certain new and useful Improvements in Plotting-Indicators, ofwhich the following is a specification.

This invention relates to a novel system adapted for use on war vesselsto indicate to the plotting room the bearings of the target. Theplotting room on a war vessel is located down in the hold far below thewater line and `it is here that the battle maneuvers are laid out on axed chart, so that the chart will not only show the past and presentpositions of the ship and target, which includes the range and bearingsof the target, but will predict the future range and bearings for apredetermined length of time. Since the plotting operator is withoutmeans Ao-f obtaining the necessary data directly, it is obvious thatsuch data must be transmitted from the points at which it is obtained.

My invention relates especially to means for transmitting the targetbearings from the target bearing telescope to the plotting room in thebest possible manner.

The drawings illustrate several forms which my invention may assume.

1 1 of Fig. the arrows. y

Fig. 2 is a plan view thereof, partly broken away and on a smallerscale.

Figs. 3 and 4 are plan views of two modifications.

Fig. 5 is a wiring diagram, showing the complete system.

Fig. 6 is a detail of Fig. 1.

Fig. 7 is a plan View of a target bearing telescope with my transmitterattached, parts being broken away for clearness.

Fig. 8 is an elevation of the transmitter detached. l

My system embodies as a fundamental principle the transmission of thebearings 2, looking in the direction of Plv by visual means, asdistinguished from the prior, auditory systems. It comprises essentiallyan indicator 1, adapted to be placed in the plotting room, which I termthe plotting indicator and a transmitter 2 for actuating said indicator,connected preferably directly to the target bearing telescope 3 on theship. This transmitter may hence appropriately he termed the targetbearing I transmitter. A third instrument is also necessary for thc bestresults, namely, an azimuth transmitter 4, preferably actuated by agyro-compass (See Fig. 5.)

My preferred form of plotting indicator is shown in Figs. 1, 2 and 6. Inthese figures, `6 denotes a suitable casing, closed at the top by atransparent cover 7, which is held in place by the 'bezel 8. lVithin thecasing is mounted all of the movable apparatus, including the indicatingdials. The actuating means comprises a plurality of repeater motors, 9vand 10 of any type, preferably ofthe well known class shown in Fig. 5.Motor 10 is designed to be connected with the azimuth transmitter 4 onthe master compass 5, but should be con- 'nected backwardly thereto, forreasons 17,"which represents Vthe points of the comVVVV i pass, andhence is in effect a dummy compass card.

The reason why it is necessary to connect the motor 10 so as to rotatedial 16 in the opposite direction from the direction in which the mastercompass and the ordinary 'repeaters turn will now be apparent, sincewhat the master compass does when a ship turns 1n a. clockwise directionis to turn counterclockwise so that if it is desired to get bearingtelescope but also by the posimitter attached is shown in Fig. 7^. Theteletion of the ship itself. The motion of the scope proper is securedto a rotatably two motors 9 and 10 must hence be combined mountedannular base 31. Secured to this to drive said index 20. The preferredbase are the worm 32, with its actuating method of accomplishing thisresult is by hand wheel 33, a push button 34, and a large 70 interposinga differential gear train. The gear 35. On the fixed portion of the sutdrawings show the use of a bevel gear epiporting standard, thelarge'worm wheel 36 is secured with which worm 32 meshes. On

cylic train, with onebevel' gear 21 secured to gear 19, and the oppositebevel gear 22 top of the standard a fixed scale 50 is provided tocoperate with suitable indications 75 secured to gear 12. The planetaryarm 23,

of the train is secured to the shaft 24, which 51 on the rotatable base.Also secured to carries a pinion 25 adjacent its lower end. said fixedstandard is the transmitter 2,

A second large gear Vwheel 2G meshes With shown in detail in Fig. 8. Itis provided said pinion and is mounted on a central with a pair ofdriving pinions37 and 38,

shaft 27 extending freely through sleeve 15 both of which mesh with saidgear A 80 and carrying adjacent its upper engl the gear 39 is fixed tothe shaft of pinion 37, while on the shaft of pinion 33, a gear' 40target bearing index 20.

The modification shown in Fig. 3 is very is loosely mounted, but isconnected to said similar, except that instead of using a difshaftthrough a spiral spring 41. Both ferential gear train to combine themotions gears 39 and 40 mesh with a. common ping5 of the two motors, themotor 9 is mounted ion 42, which turns directly the commutator directlyon the large gear wheel 14 driven 43. By proi-"iding this peculiarconstruction, by motor 10, so that the gear 26', driven di- I am enabledto do away with errors arisrectly from motor 9, receives a combined ingfrom the back lash of the gears, since the motion' from both motors asbefore. spring always presses the two pinions firmly 90 In Fig. 4,however, a somewhat different against the same side of the teeththroughdesign is illustrated. According to this moolout the gear train.The commutator 43 or ification the outer fixed dial 1'7 is designedtransmitter proper may be of any type deto serve as a lubbers scale,while the inner signed to actuate the type of repeater modial 16actuated from the master compass, tors used. Fig. 8 shows it as a threesec- 95 becomes a repeater compass card. showing, tioned drum, eachsection having two conif the instrument is correctly placed, the ductingstrips '44 of about 900, the two strips true meridian. According to thismodifibeing diametrically opposite and spaced by cation, then, thecompass motor 10 drives insulation. The strips on each section are thedial 16 directly as before but is conplaced about 30O ahead of theposition of 100 y nected so as to turn it in the same direction thestrips on the preceding section, and are Eil all grounded to the frame.A brush 45 is provided for each section. The action of this transmitteris well shown in Fig. 5, in which three contacting points are shown,lo?` out the interpolation of a compensating facwhich are arranged to bebrought into suctor from motor 10, since the lubbers line, cessiveengagement as the transmitter is .-accor.ding.-to this modification, isfixed... .Wactuated. ""In comparing ihethree 'modifications, it Thebutton34 is p should be noted that the same general resignaling theplotting room when the true 11a sults are secured in each instance,namely bearings of the target are obtained. It the indication to the.plotting board opcrcloses a circuit through a miniature lamp 4G ators ofthe heading of the ship in azimuth, on the plotting indicator, so thatthe operthe bearings of the target in azimuth and ators may` know whento begin laying out the bearings of the target with respect to thebattle. An electric circuit is brought li the ship. But the form shownin Figs. 1 into the button 34 through slip rings 47 and 2 possesses theimportant advantage of and brushes 48. having the points of the compassfixed with In order to synchronize the readings of respect to the shipinstead of fixed in azithe plotting indicator with the master conmuth.This advantage arises from the fact trolling instruments, settinghandles 53 and 12C that the chart on the plotting board is nor- 54 maybe employed. Each handle is promally fixed on the ship and the points ofvided with a crown gear 55 and is normally 'the compass are arbitrarilypositioned therefv pressed outward by a spring 5G. An auxo'n accordingto the usual custom, so that if iliary shaft 57 (see Fig. (l) isprovided to the plotting indicator is also provided with carry the gearsadapted to engage said 125 fixed compass markings, such as scale 17,crown gears. On said shaft is mounted a the lines on the chart mayalways be laid gear 58 driven from gear 12 and a gear 59 out parallel tothe lubbers line scale and driven from gear 19. Secured to gear 58target bearing index on the indicator. is a gear 60 with which the crowngear of A target bearing telescope 3 with a transone of said settinghandles is adapted to 130 that the master compass turns, that is so thatthe instrument becomes a. true repeater compass. Also, the motor 9,drives the indeX 20" directly through the gear 26, withmesh on beingpushed in, While secured to gear 59 is a corresponding gear G1 for theother handle.

The operation of my system is as follows: The plotting indicator isfirst synchronized with its controlling instruments. This is preferablydone as far as the target bearing index is concerned by bringing boththe telescope and indeX to zero on the lubbers scale. The operator ofthe telescope then starts to bring his instrument to bear on the target.At the same time the index 20 reproduces the movements of the telescopein the plotting room by the electric connections explained above. Assoon as the telescope operator has obtained the coi'- rect bearings, hepresses button 34, thus signaling the plotting room that the index is onthe target.

The lubbers scale in Figs. l and 2, or the compa-ss card in Fig. 8 isconstantly maintained in the correct position by the master compass, sothat as soon as the target is spotted. and the range found, thc plottingcan be commenced. From this chart, the

. bearings and range are predicted and sent out to the turrets.

In the preferred forms of the invention I (Figs. l and 3) a peculiarfunction ofthe setting handles arises. This is due to the. fact that arotation or movement of one of the'indicating-elements produces a torqueor tendency to move the other element through physical contact such asthe reactions of the differential gear train or its equivalent. Toprevent the other element from moving when setting one element With the4corresponding handle, the operator simply pushes in on the other handleand holds it. Thus both handles are used simultaneously, but fordifferent purposes in this instance.

In accordance with the provisionsof the patent statutes, I have hereindescribed the principleA of'ope'ration of 'inywinventiom together withthe apparatus which I novv consider to represent the best embodimentthereof, but I desire to have it understood that thel apparatus shown isonly illustrative and that the invention can be carried out by othermeans. Also, While it is designed to use the various features andelements in the combination and relations described, somel of these maybe altered and others omitted Without interfering with the more generalresults outlined, and the invention extends to such use. Thus, inaddition to its use in the plotting room, my invention also possesses animportant advantage as a steering` compass. In battle formation, it isjust as important for the pilot to keep the target bearing angle asconstant as possible as it is for him to maintain his course. With myinventionbefore him, this becomes a simple matter, since all that needbe done is to hold 65 the angle made by pointer 20 on dial 16 constantin the forni shown in Fig. 2, or in Fig. 4 to maintain the reading'ofpointer 20 on scale 17 constant. No additional instrument is required,as the saine indicator shows the' course and the target bearings. 7^

-nation with a master compass and a target a@ bearing telescope, of aAfixed indicator, a plurality of movable indicators adapted to beautomatically controlled by said compass and telescope all of saidindicators being conjointly readable, whereby the bearings of 35 thetarget both with respect to the meridian and to the lubbers line of theship are shown simultaneously.

3. A telemetric azimuth indicating device for use on shipboardcomprising an indica- 9c tor normally fixed on the ship and adapted. toshow arbitrary points in azimuth, and a lubbers line indicator rotatablymounted adjacent said azimuth indicator and adapted to be actuated froma master compass. 95

4. A plotting indicator comprising a fixed dummy compass scale, arotatable lubbers line indicator, a target bearing indicator andautomatic means to operate each of said indicators, whereby the bearingsof the ship and target are shown both with respect to each other andwith respect to a fixed chart. 5. In a target bearing indicating system,the combination with a sighting instrument and a compass, each beingprovided with a 105 transmitter, a repeater motor actuated from eachtransmitter, a lubbers line indicator mconnected to saidcompass motor,Vvand a target-bearing indicator connected to bothi'f said motors.

6. In a target bearing indicating system, the combination with asighting instrument and a compass, each being provided with atransmitter, a motor actuated from each transmitter, a lubbers lineindicator geared to said compass motor, a target bearing indicator, anda. differential gear train conllii ynecting said last named indicator toboth of said motors.

7. In a ships indicator, the combination 12e with a sighting instrumentand a compass, each being provided With a transmitter, a motive meansactuated from each transmitter, a. ships heading indicator and a. targetbearing indicator geared to said means anda manual setting means foreach indicator, one of said means being adapted to prevent one indicatorfrom being turned'by the setting of the other indicator.

8. In an indicator for ships, a plurality of 13:

concentrically mounted indicators, a plurality of repeater motors gearedto said indicators, and a manual setting means for each indicator, oneof said means being, adapted to prevent an indicator from being turnedby the setting of another of said indicators.

9. In an indicator for ships, a plurality of concentrically mountedindicators, a plurality oi repeater motors geared to said indi-v cators,and to each other through diiierential gearing, and a manual settingmeans for each indicator, one of said means being adapted to prevent anindicator from being turned by the setting of another of saidindicators.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses, this 12th day of November 1914.

ELMER A. SPERRY.

Witnesses:

EARL W. CHAFEE, F. R. ALLEN.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents Washington, D. C.

